The present invention relates to a storage system for managing a level at which a file is stored in accordance with tag information representative of file contents and file access frequency information and a file layer management method, respectively in layer storage environment for file levels.
Recently, demands for online storage such as content depots are increasing as storages for reposition/distribution of digital contents. Layer storage environment for file levels has been paid attention, such as relocating files in accordance with a file access frequency for the purposes of storage optimization.
In response to high momentum for protection of the global environment, information technology industry also increases the efforts against reduction in consumption power of apparatus. There is therefore increasing interest to reduction in a consumption power of a storage apparatus. Introduction of MAID (Massive Array of Inactive Disks) technology is progressed which can suppress a consumption power of a storage apparatus through spindown/spinoff of disks loaded in the storage apparatus. For example, JP-A-2000-293314 Publication (corresponding to U.S. Pat. No. 7,355,806B2, Hakamata et al.) discloses a power supply control method of making a host computer control a power supply in accordance with an access frequency to a storage apparatus.